Gun perforating apparatus for wells



May 1, 1962 CIB. coRLEY, JR.; ETAL 3,032,109

GUN PERFORATING APPARATUS FOR WELLS 2 Sheets-Sheet 1 Filed Oct. l2, 1959 w OJ INVENTORS. F|G.3. CHARLES B. coRLEY JR.,

JOHN w. KENNEDAY, BY GILBERT H. TAuscH,

MARTIN E. TRUE,

@MJL www ATTORNEY.

May 1, 1962 c. B. coRLEY, JR., ETAL 3,032,109

GUN PERFORMING APPARATUS FOR WELLS 2 Sheets-Sheet 2 Filed Oct. l2. 1959 T H. TAuscH, N E.TRu

FIG. 5.

United States Patent Otitice 3,@32Jh9 Patented May 1, 1962 GUN EERFORATING APPARATUS FOR WELLS Charles E. Corley, Jr., Houston, John W. Kenneday,

Corpus Christi, Gilbert H. Tausch, Houston, and Martin E. True, Tyler, Tex., assignors, by mesne assignments, to .lersey Production Research Company, Tulsa,

Okla., a corporation of Delaware Filed Get. 12, 1959, Ser. No. 845,764 1 Claim. (Cl. 166--55.4)

This invention relates to oil and gas wells. More particularly, this invention relates to methods for perforating a cased well.

For certain operations in oil and gas wells, it is often desirable to eliminate the need for a wireline. For example, when a well is located offshore, it is extremely desirable that the various tools which are put into the well and located in the tubing be so placed without requiring the use of a wireline. It is very diicult to lower tools into a well by means of gravity or by wireline when the well is located offshore. The tubing extends from the shoreline to the offshore location and often has many bends or curves through which the tools must be passed.

After the tool, such as a perforating tool, has been placed into the offshore well and the perforating operations completed, it then becomes necessary to remove that portion of the perforating tool which remains extending from the lower portion of the production tubing. Here again, if wireline operated devices are used to remove this portion, undue friction occurs, interfering with the etlicient operation of the removal procedure. These wireline tools are only with diiliculty forced through the bends in the piping leading from the onshore location to the offshore well.

The method to be described herein is a new and improved method for perforating a cased well having production tubing arranged in the well with its lower extremity at a point above the area to be perforated. In performing this method, a wireline or pulling tool having a wireline connected thereto is never required.

Briefly described, the method comprises rst pumping a perforating member down the well through the production tubing to seat the upper portion of the perforating member in the lower end of the production tubing. Thus, the gun portion of the perforating member extends from the lower portion of the production tubing to a point adjacent the area to be perforated. The upper portion of the perforating member contains a tiring switch. After the perforating member has been properly placed, a firing member is then pumped down the well through the production tubing to engage the upper portion of the perforating member and close the firing switch. The desired area is thus perforated. Finally, reverse circulation is applied to remove the firing member and that portion of the perforating member remaining attached to the firing member.

The invention as well as its many advantages will be further understood by reference to the following detailed description and drawings in which:

FIG. l is an elevational view showing a well located offshore with the perforating member located in position within the bottom portion of the production tubing;

FIG. 2 is an elevational View showing the tiring member being pumped through the production tubing to engage the perforating member and re the perforating gun;

FIG. 3 is an elevational view showing the tiring member engaging the fishing neck of the perforating member;

FIG. 4 is an elevational view showing the removal of the tiring member and the remaining portion of the perforating member by reverse circulation;

FIG. 5 is a view, partly in elevation and partly in section, showing the firing switch assembly, in detail;

FIG. 5A is -a continuation of FIG. 5;

FIG. 6 is a cross-sectional view taken along lines 6-6 of FIG. 5;

FIG. 7 is a sectional view of the ring chamber;

iFIG. 8 is a view, partly in elevation and partly in section, of the knuckle joints;

FIG. 9 is an enlarged sectional view of the fluid bypass and rupture disk shown in FIG. 5; and

FIG. 10 is an elevational view showing a second embodiment of perforating member suitable for use in carrying out our new method.

Referring to FIG. l, a borehole is shown penetrating the earth and traversing subsurface formations 10 and 11. The borehole includes the usual casing 12 which is cemented to the sides of the borehole by means of cement 14.

Production tubing 16 extends into the well and terminates at a point above the formation 10. The producltion tubing 16 extends through a wellhead 18 and connects with a short radius bend pipe 20. The short radius bend pipe 20 is coupled to a laterally extending conduit 22 by means of a coupling member 24. The well, short radius bend pipe 20, and laterally extending pipe 22 are all below the wa-ter line 26.

Pipe 22 extends to a remote location, such as a central production platform or to the shore 28. A lubricator 30 is connected to the pipe 22. Valves 32 and 34 are provided at the extremities of lubricator 30.

Extending from the lubricator 30 is a conduit 36. Fluid may be pumped into the lubricator 3i), laterally extending pipe 22, bend 20, and production tubing 16 by means of pump 38.

A second laterally extending pipe 40 is connected to the wellhead 18 and extends to a pump 42 located on the shore 28.

FIGS. l to 9 show a perforating member `44 which is pumped from the lubricator 30 through the laterally extending pipe 22, short radius bend pipe 20, and production tubing 16 until it rests upon a no-go shoulder 46 provided adjacent the lower end of the production tubing 16. The perforating member 44 includes in the upper portion thereof swab cups 48 and 50 which are used to pump the tool into the well. A fishing neck 52 is provided at the upper extremity of the perforating member 44. Also provided on member 44, below the cup 50, is a rio-go ring 51.

A normally open firing switch mechanism 56 is provided in the perforating member 44. The details of the firing switch mechanism are shown in FIG. 5. A small piston member 41 is shear pinned by shear pin 43 extending from the sides forming bore 54 and through piston 41. The piston shaft 45 extends from the piston member 41 to a point within chamber 47 and is biased upwardly by compression spring 49 disposed about shaft 45. Electrical contact 51 is mounted on shaft 45 adjacent the lower extremity thereof and insulated from shaft 45 by insulator 53. A second electrical contact 55 is mounted to a side of chamber 47. The ring mechanism may be tired by a member to be subsequently pumped down the tubing 16 and having an elongated probe portion which will extend into the bore 54 to break the shear pin and move contact 5l into engagement with contact 55.

The portion of the perforating member 44 which extends below the lower end of the production tubing 16 includes a spacer member 58 which is connected into the assembly by knuckle joints such as 6). The length of the spacer member 58 and the provision of knuckle joints 60 permit the tool to pass through the bends and joints in the tubing system such as the short radius bend 20. The length and number of the knuckle jointed members 58 is predetermined to locate the gun portion 62 of the perforating member in the desired area to be perforated, which in FIG. 1 is shown to be the producing formation 10. The gun portion 62 is made of a resilient material, such as rubber. If it is desirable to perforate the lower formation 11, it is obvious that a plurality of spacer members 58 would be required. The proper length has been previously determined by methods well known to those skilled in the art. v

A fluid by-pass port 64 extends through the mandrel 65. A shear disk 66 is mounted across the by-pass port 64 and kept in place by slip ring 617 `(see FIG. 9). i Electrical conductors 68 extend from the tiring mechanism 56 through the mandrel 65 and the knuckle jointed members 60 to the tiring chamber 76'. Aplurality ofbatteries inbattery section 72 provide an electrical current through conductors 68 when the switch assembly 56 is actuated. Conductors 68 have their lower ends connected to a ring means such as blasting cap 73 (see FIG. 7). When current is fed to tiring cap 73, the powder 74 in tiring chamber 70` is ignited which, in turn, ignites prima cord 76 leading to a plurality of shaped charges 78. Thus, when the tiring mechanism is actuated, the shaped charges 78 in the gun portion 62 will be red to perforate the casing 12, cement 14, and formation 10.

After the perforating member V44rhas been properly located, the tiring member is then pumped down the well through the production tubing 16. As shown in FIG. V2, the tiring member 80 includes an upwardly facing swab 82 and a downwardly facing swab 84. Included as a portion of the tiring member 80 are latching members 86 and a firing pin 88. The tiring pin 88 is centrally located on the bottom of the tiring member 80.

Prior to the pumping of the ring member 80,y down the production tubing 16, an increased pressure is applied against the disk 66 to expel the disk from by-pass 64, thus providing a uid by-pass which permits the retrieving tool to be pumped down the well into position.

FIG. 3 shows the engagement of the tiring member 80 with the ishing neck 52 of the perforating member 44. The tiring pin 88 has contacted theY piston member 41 to lire the shaped charges 78 through the casing 12, cement 14, and into the subsurface formation to provide perforations 90. Subsequent production from formation 10 will ilow oil and gases through the perforations 90, the production tubing 16, bend 20, and later-ally extending pipe 22 to the shoreline.

Reverse circulation is then applied to thewell by pumping fluid, by means of pump 42 (see FIG. l), through laterally extending pipe 40, the annulus between the production tubing 16 and casing 12, and then up the inside of production tubing 16, short radius bend 20, and laterally extending pipe 22. By this means, the ring member 80 and the remaining portion of the perforating member 44 are removed to the onshore location,

4 FIG. 10 shows a second embodiment of perforating member which can be used in carrying out our newk method. Referring to FIG. 10, a flexible connection 160 interconnects the battery section 72 and the firing chamber 70. Electrical conductors 68 extend from switch assembly 56, through the -exible connection 100 to tiring chamber 70. An upwardly facing cup 102 is used to pump the tool into the well.

In operation, the perforating member is rst pumped down the production tubing and located in its proper position. Then the disk 66 is ruptured and the firing member is pumped down the production tubing to close the contacts 51 and 55 to perforate the subsurface formation. The reverse circulation is applied to remove the tiring member 8G and the portion of the perforating member which Vremains after the perforations have beenY made.

We. claim:

A system for useV in perforating a cased well having production tubing arranged in the well with the lower extremity of the production tubing at a point above the area 'tov be perforated and the production tubing also having internal landing means comprising: a perforating member having a fishing neck and shaped charges positioned therein; said perforating member being provided with packing and engaging means so that when direct circulation is started, the perforating member is pumped down the production tubing and located in the production tubing by the engagement of said engaging means with said internal landing means; a normally open tiring switch mechanism located in said perforating member; and a separate and disconnected tiring member having packing means shaped so that the firing member will move in the same direction as the direction of uid flow, said firing membery having means for closing the normally open tiring switch mechanism in the perforating member and latching means for engaging the fishing neck of the perforating member so that after the perforating member is located in Vthe production tubing, the ring member is pumped down the tubing to close the tiring switch mechanism t'o perforate the desired area and engage the fishing neck of the perforating member, and then reverse circulation initiated to remove the tiring member and that portion of the perforating member remaining attached to the rng member.

References Cited in the le of this patent UNITED STATES PATENTS 2,638,981 Bannon etal May 19, 1953 261905123 Kanady Sept. 28, 1954 2,705,920 Kanady Apr. 12, 1955 2,766,828 Rachford Oct. 16, 1956 2,776,010 Rike Jan. 1, 1957 2,804,150 lFuson Aug. 27, 1957 2,805,718 Tausch Sept. 10, 1957 2,876,843 Huber Mar. 10, 1959 

